or just "expressing"? Showing, present, having as alternatives, but unsure.

One must presume that long and short arguments contribute to the same end. - Epicurus...except casandra's that did belong to the funniest, most interesting and imaginative (or over-imaginative?) ones, I suppose.

one animal is deficient in XY antigen or gene. Then, we refer to them as XY-deficient animal. What is the opposite of that?

wild-type with respect to XY, XY-normal, XY-positive...

for wild-type and XY-normal : I cannot use these because as I mentioned before, they are not transgenic but naturally lack the antigen. So, for the species, refering them as 'wild' or 'normal' will not be appropriate.

In genetics, "wild-type" does not imply "as found in nature", it implies the type to which you are comparing. Many people make or isolate mutants of E. coli DH5-alpha, and then compare those mutants against the "wild-type" DH5-alpha from whence they came, but the parental strain is far from natural (genotype: fhuA2 Δ(argF-lacZ)U169 phoA glnV44 Φ80 Δ(lacZ)M15 gyrA96 recA1 relA1 endA1 thi-1 hsdR17).

It may still not be an appropriate phrase for you needs, but I thought I'd just clear that up a bit...

one animal is deficient in XY antigen or gene. Then, we refer to them as XY-deficient animal. What is the opposite of that?

wild-type with respect to XY, XY-normal, XY-positive...

for wild-type and XY-normal : I cannot use these because as I mentioned before, they are not transgenic but naturally lack the antigen. So, for the species, refering them as 'wild' or 'normal' will not be appropriate.

I would go for option 3. 1 and 2 don't sound like especially good English (a bit clunky or perhaps just poor grammar), and 4 might confuse, if I understand you correctly. The untreated animals do not have XY and treated ones do, right? The implication of Option 4, however, is that the XY-deficient animals have had something taken away. As another alternate, you might be able to use "transgenic" instead of "XY-positive" (or containing or expressing)...

Heart disease kills more women than breast cancer, but heart attack symptoms differ from men's symptoms. Get to know your heart... it could save your life.

one animal is deficient in XY antigen or gene. Then, we refer to them as XY-deficient animal. What is the opposite of that?

wild-type with respect to XY, XY-normal, XY-positive...

for wild-type and XY-normal : I cannot use these because as I mentioned before, they are not transgenic but naturally lack the antigen. So, for the species, refering them as 'wild' or 'normal' will not be appropriate.

I would go for option 3. 1 and 2 don't sound like especially good English (a bit clunky or perhaps just poor grammar), and 4 might confuse, if I understand you correctly. The untreated animals do not have XY and treated ones do, right? The implication of Option 4, however, is that the XY-deficient animals have had something taken away. As another alternate, you might be able to use "transgenic" instead of "XY-positive" (or containing or expressing)...

mm, I have not been able to put my question correctly. There is gene for XY gene in mice and not in rats. So, mice expresses XY gene but not rats. (naturally - no genetic manipulations or any other interventions).

So, wanted to find the right term to put a caption. I have the description in the text but want to label the figure with just 1-2 words.

one animal is deficient in XY antigen or gene. Then, we refer to them as XY-deficient animal. What is the opposite of that?

wild-type with respect to XY, XY-normal, XY-positive...

for wild-type and XY-normal : I cannot use these because as I mentioned before, they are not transgenic but naturally lack the antigen. So, for the species, refering them as 'wild' or 'normal' will not be appropriate.

I would go for option 3. 1 and 2 don't sound like especially good English (a bit clunky or perhaps just poor grammar), and 4 might confuse, if I understand you correctly. The untreated animals do not have XY and treated ones do, right? The implication of Option 4, however, is that the XY-deficient animals have had something taken away. As another alternate, you might be able to use "transgenic" instead of "XY-positive" (or containing or expressing)...

mm, I have not been able to put my question correctly. There is gene for XY gene in mice and not in rats. So, mice expresses XY gene but not rats. (naturally - no genetic manipulations or any other interventions).

So, wanted to find the right term to put a caption. I have the description in the text but want to label the figure with just 1-2 words.

Best will be then

Mice : XY-postive >> Rat : XY-negative

or

Mice : XY-expressing >> Rat : XY-deficient.

In that case, I'd go with positive/negative, because the text will have gone into all the fiddly detail.

Heart disease kills more women than breast cancer, but heart attack symptoms differ from men's symptoms. Get to know your heart... it could save your life.